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The 2009 Super Sport since a new ingredient was introduced in January 2009 (January B, March, May and June) is noted for its high torque levels. For example, on my Yuriy Blazhevych 4:1 winder, the older Super Sport torques up to 5.5-6 while the 2009 rubber can get up to 7-7.5 (which is roughly half the common winder torque values).
My measurements of energy (60 Lb break in + Bradley’s method to 86-78 Lb pull) indicate that the 2009 rubber has higher energy than the previous Super Sport. Others (Carrol Allen and Omeri Sirkis in Israel) get roughly the same overall energy.
The higher torque has caused problems to flier who activate their VIT (and AR) off the back peg loaded with a spring (Jerry McGlashan and Carrol Allen) by delaying the VIT (and AR).
What I discover is the 2009 rubber requires more left deflections of the AR1 (burst) and AR2 (mid climb correction). I made such adjustments on one of my electronic models (the one I flew at the Nat’s flyoff) and evidently it flew very well. However, flying it with older rubber (December 2008) this Saturday at Geneseo, with the new AR1+2 settings almost ended with a disaster: the model did not turn at all, hung in the propellor, then went over the top and looped, fortunately clearing the ground,=. It then resumed its cruise climbing in buoyant air with a happy ending. The next flight I adjusted the AR1 and AR2 back to their original settings and the model flew fine with the December 2008 rubber.
Evidently, the 2009 rubber requires deflecting both AR1 and AR2 more to the left and possibly a larger wing twist in the early part of the climb. These changes should be undone when switching back to the older rubber.
Have others had similar experiences?
Does the 2009 rubber have more energy?
Do models climb higher with the 2009 rubber than with older Super Sport?Speaking to other F1B fliers, it turns out that the 2009 rubber required two other modifications. First, some reduced the wing twist (single wining wiggler, left wing). This was done to avoid the model from rolling immediately to the left at launch. No AR changes were made.
Second, another flier increased the prop’s pitch – as the motor runs of the 2009 rubber tend to be shorter. However, this trim was flown only in very windy conditions – so it’s not clear whether other trim changes might be required.
I have some on order which I intend to use primarily on lockdown models. Do you think there are substantial trim changes needed for the new SS?
Slightly less wing wiggler. I attribute this to the model flying faster and the trim having more influence.
Randy,
It’s important to specify what kind of rubber models you are flying. My posts only cover auto surface F1B models with 30 grams motors; Bill’s models fall into this category. The higher torque would definitely impact AMA models with heavier motors.On the other hand, it might be irrelevant for 10 gram motors. Hope fliers who fly such models would share their experiences.
I flew F1G at the british nationals with January 2009 Super Sport and my impression it was the best yet.I have only used SS in the past.I found the trim needed to be no different,but it climbed better.You say Jan B in your first post.Were there 2 batches in January.I have ordered some of a later batch which I will be able to test soon.I will post my results.
DocJames,
There were two January 2009 batches. Evidently they ran out of a component and bought a substitute from a new supplier. The second batch is called January “B”. The new component was included in all the subsequent 2009 batches.You might want to query FAI supply tabout what batch you have. Alternatively, measure its torque relative to older Super Sport motors.
I have just ordered some June 2009 but wont be able to use and test it till I am back home in 2 weeks.More news then.I will compare the 2. It will all be a more level playing field when Tan 2 stocks run out.
I will have no excuse then!!
We always have a post mortem in the local pub,the evening after comps.The excuses get more reasonable as the alcohol flows.It usually goes like “if only…..”
I have been moaning that I am disadvantaged by not having the best Tan2.I will have to find another excuse now.
There are lots of competitions here in September and October,so I am hoping for some good weather.I had a couple of test flights with the 6/09 yesterday and it is indeed good stuff. I flew it in a locked down F1G Burdov and it performed very well. On a 10 strand motor I wound to 525 turns @ 25 OI of torque. On a much shorter 12 strand motor I wound to 420 turns and 35 OI of torque. I didn’t measure it but the rubber must be thicker as it took a significantly shorter motor to make 12 strands than any of my other rubber.
This latter motor had a more pronounced power burst as you would expect which the airplane handled pretty well. The first motor resulted in a long motor run with pretty good climb during the cruise. I’m not so certain that the longer run motor isn’t facilitated by this new rubber whereas I wouldn’t find that approach competitive with normal rubber. Keep in mind that I didn’t wind to destruction with either motor so there may be quite a bit more winds available. I did try to wind the shorter motor again for a second flight but a couple of the strands parted and I abandoned the idea. Must have been pretty close on that motor.
With 10g of rubber the most turns I ever get with my Super Sport is 420.
I normally wind to about 400.I once got up to 470 with 10g of Tan2 and 12 strands.If I can get to 500 with this new stuff I shall be home and dry,or rather O.O.S. I am looking forward to the next few comps.Hi Guys ( and Gals) I have been reading the mail but have just been able to log on. I have a rubber tester that I built way back in the 70’s that plots a curve of tension verses elongation on a sheet of graph paper. Integrating the area under the curve gives the total energy stored. I started out in the 40 gram pirelli days with stressing 16 strands of 1/4 inch rubber to 100 lbs. Since we have gone to 30 grams I scaled that back some what. With the FAI super sport I am stressing it to 5600 psi.
To get to the point, I don’t see much difference in total energy storage between the new 2009 rubber and some April 2007 rubber< both average about 230 ft-Lbs for a 30 gram motor. What I do see is that the new rubber can be stressed to a some what higher level before breaking. The other thing is that the May 2009 rubber varies a lot in thickness. Measuring the length of 10 gram coupe motors they vary from 57″ to 61″.
This is the same as varying the number of strands.I worked out a formula for the maximum torque and turns based on the length if any is interested.
Enjoy the rest of the season!
Carrol
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